Objective : Drink driving is widely recognised as a major road safety problem. In Australia, health promotion messages encourage monitoring the number of standard drinks consumed prior to driving. The pilot research aimed to investigate commuting behaviour and blood alcohol concentration (BAC) of diners, including intended-drivers, at Sunshine Coast restaurants. Methods : Five hundred and forty-four diners (n = 260 males) consented to participate in a brief interview and to use a b eathalyser device to measure their BAC. Results : Forty percent of participants advised they don’t drink and drive (34% of males, 45% of females; 67.25% of <17-20 years, 30.5% of 50-59 years), and of the remaining participants, 75% advised they count the number of their drinks (69% of males, 84% of females; 32% of <17-20 years, 82% of 50-59 years) while 10% of participants monitored their BAC by how they were feeling (12% of males, 6% of females). Thirty-seven percent of participants said it was easyvery easy to estimate their BAC (41% of males; 33% of females; 21% of <17-20 years, 43% of 50-59 years). The actual BAC was less than expected for 56% of participants, with one third underestimating BAC and some intended-drivers having an actual BAC in excess of the 0.05 limit. Conclusions Given the proportion of diners who reported they count the number of drinks, or use feelings as a way to gauge BAC, coupled with the considerable proportion who underestimated their BAC, a safer public health message is to avoid driving if you intend to drink. In addition, targeted intervention for experienced drivers (and, arguably, drinkers) appears warranted as every participant aged less than 21 years who stated they would drive home indeed had a zero BAC. Interestingly every female driver who stated they would be driving home also had a legal BAC, suggesting gender-specific intervention.